Prenatal prognostic factors for isolated right congenital diaphragmatic hernia: a single center’s experience

Background Right-sided congenital diaphragmatic hernia (RCDH) is relatively rare compared with left-sided congenital diaphragmatic hernia (LCDH). Clinical data of RCDH, especially with respect to antenatal prediction of neonatal outcome, are lacking. The aim of this study was to report the treatment outcomes of patients with antenatally diagnosed RCDH and to evaluate the predictability of observed-to-expected lung area-to-head circumference ratio (O/E LHR) for perinatal outcomes, focused on mortality or extracorporeal membrane oxygenation (ECMO) requirement. Methods We retrospectively reviewed the medical records of newborn infants with isolated RCDH. We analyzed and compared the clinical and prenatal characteristics including the fetal lung volume, which was measured as the O/E LHR, between the survivors and the non-survivors. Results A total of 26 (66.7%) of 39 patients with isolated RCDH survived to discharge. The O/E LHR was significantly greater in survivors (64.7 [+ or -] 21.2) than in non-survivors (40.5 [+ or -] 23.4) (P =.027). It was greater in survivors without ECMO requirement (68.3 [+ or -] 15.1) than non-survivors or those with ECMO requirement (46.3 [+ or -] 19.4; P = .010). The best O/E LHR cut-off value for predicting mortality in isolated RCDH was 50. Conclusions The findings in this study suggest that O/E LHR, a well-characterized prognostic indicator in LCDH, could be applied to a fetus with antenatally diagnosed RCDH. A large cohort study is required to verify the association between O/E LHR values and the graded severity of RCDH. Keywords: Congenital diaphragmatic hernia, Right-sided congenital diaphragmatic hernia, Observed-to-expected lung area-to-head circumference ratio, Extracorporeal membrane oxygenation